<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>导航栏</title>
    <style>
        .tree-menu{
            position: absolute;
            background-color: khaki;
        }
        .nav {
            margin: 0 auto;
            border: 2px solid #00CED1;
        }

        ul,
        li {
            margin: 0;
            padding: 0;
            list-style: none;
        }

        ul {
            display: flex;
            flex-direction: row;
            flex-wrap: wrap;
        }

        li {
            border: 1px solid;
            width: 100px;
            text-align: center;
            margin-top: 10px;
            margin-bottom: 10px;
            flex: auto;
        }

        .hide {
            display: none;
        }


        .menu {
            display: inline-block;
        }
    </style>
</head>

<body>
    <a>
        <span class="tree-menu">
            <ul class="nav">
                <li>AAA</li>
                <!-- <li>BBB</li> -->
                <li>CCC</li>
                <!-- <li>DDD</li> -->
                <li>EEE</li>
            </ul>
        </span>
    </a>

    <!-- <div>
        <span class="menu icon">123</span>
        <span class="menu name">abc</span>
        <div class="menu list">
            sss
        </div>
    </div> -->
</body>

</html>